1. Field of the Invention
Decompression sickness, or "the bends" caused by increased environmental pressure is commonly seen in divers using scuba (self-contained underwater breathing apparatus).
Divers using scuba gear must control their rate of ascent towards the surface to avoid the bends. A device to indicate the rate of ascent is needed, the instant invention discloses a simple device that indicates the rate of a diver's ascent.
2. Description of the Related Art
U.S. Pat. No. 3,121,333 issued to Alinari in 1964 describes an indicating instrument for divers that accurately indicates the decompression stoppages as a function of the immersion accomplished. The instrument comprises a bellows subject to the hydrostatic pressure from the liquid in which it is immersed coupled to a pressure gage for measuring the instantaneous pressure. U.S. Pat. No. 4,820,953 issued to Sauballe et al in 1989, describes a rate of ascent monitor for divers that uses a sound transducer with velocity characteristics to sense a rate of pressure changes.